Gawd I'm a broken record on this subject...
BEFORE you do ANYTHING ELSE
Go into the "Software Media Manager" and remove any disks that you do not have on hand, or bettery yet remove ALL of the CD's!
Then exit out and go to this site:
http://www.zebulon.org.uk/urpmi_en.html
Follow the directions for setting up your URPMI sources.
Do this as ROOT!
Once done merely type
urpmi gaim
and everything will be taken care of for you.
You can also change to the directory where you downloaded that file and type
urpmi aim*.rpm
and let it work it's magic.
Note once the prompt comes back wait a few minutes as Linux churns away in the background updating the menus to reflect any changes.
AFTER you have done all of this, go into the "INSTALL SOFTWARE" gui and you'll find a treasure trove of new software which is now available to you.
All of this software can be installed my merely putting checkmarks in front of what you want, and there is a LOT of great stuff including AIM clients like GAIM and Kopete (which supports AOL, Yahoo, Microsoft, etc. messengering services at the same time!).